High impact polystyrene (HIPS) is known. HIPS is prepared by grafting polystyrene onto an impact modifier such as cis-polybutadiene. HIPS has a wide variety of uses. Unfortunately, HIPS has an impact strength in the range of 1.2 to 1.5 ft. lb./inch (65 JM). It is desirable to increase the Izod impact of styrenic polymers or blends of styrenic polymers with other polymers.
Nylon is a strong polymer, which may be toughened by blending it with an impact modifier such as a functionalized rubber (e.g. maleated EPDM) as disclosed in U.S. Pat. No. 4,174,358 issued Nov. 13, 1979 to DuPont (Epstein). Nylon may also be toughened by blending it with an halogenated elastomer as disclosed in U.S. Pat. No. 4,350,794 issued Sept. 21, 1982 to Monsanto (Moncur). Neither of the above patents contemplate a major component of the composition being a vinyl polymer.
The present invention provides novel reactive polymer blends based on vinyl polymers. The blends have a good balance of properties and may be processed in an extruder.